Abstract

Motivation: Chemical-shift-encoded (CSE)-based proton-density fat-fraction (PDFF) is a highly validated biomarker of liver fat. T1 mapping has been proposed as a biomarker of hepatic fibrosis. However, the reproducibility of PDFF and T1 in the setting of concomitantly varying fat and T1 is poorly understood. Goal(s): To validate the reproducibility of CSE-based PDFF and MOLLI-based T1 mapping with concomitantly varying fat and T1. Approach: We conducted a four-center, four-vendor validation study using a quantitative PDFF-T1 phantom. Results: CSE-based PDFF had good reproducibility, although with increased bias and variability at long T1 values. The reproducibility of MOLLI-based T1 was affected substantially by the presence of fat. Impact: CSE-based PDFF demonstrated good reproducibility across four centers/vendors, at both 1.5T and 3T. Increased T1 and increased PDFF led to reduced MOLLI-based T1 reproducibility. This multi-center multi-vendor PDFF-T1 phantom validation approach may enable evaluation of improved quantitative MRI methods.